Conventional general purpose bus protocols for master-slave interfaces typically have the master recovering read data received from the slave over the bus with either the rising edge or the falling edge of a clock. However, delays introduced during transactions across the interface may cause problems with recovering the read data.
To solve these problems, conventional systems generally use one of two solutions. One solution involves tuning the interface, which may be done if the range of delays is small. The other solution involves selecting either the rising edge or the falling edge to use in recovering read data, which may be done if the delay is less than a clock period. However, when the delays are too long and/or are highly variable, these solutions may be inadequate and the master may be unable to recover the read data.
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